Multiplying Function Handles quad

Question

sarngon 2015-3-20

评论： Torsten 2015-3-20

Hi Guys , When I run this code below I get Error using * Inner matrix dimensions must agree. So whats your solution for this .

Error in f8>@(w)bb(w)*cc(w) (line 31)
  f3 =@(w)bb(w)*cc(w);

Thanks .

code:

bb=@(w) (((1+w/wr*l)*vi/ccons).^(k-1));
  cc=@(w) (2.71.^((-((1+w/wr*l)*vi/ccons)).^k));
  f3 =@(w)bb(w)*cc(w);

Answer 1

Torsten 2015-3-20

f3 =@(w)bb(w).*cc(w);

Best wishes

Torsten.

sarngon 2015-3-20

Thanks ,

Can You explain why should I use dot there ?

Torsten 2015-3-20

w is a vector, say w=(w1,w2,...,wn), and the value of your function to be integrated at positions

w=(w1,w2,...,wn) is

(bb(w1)*cc(w1),bb(w2)*cc(w2),...,bb(wn)*cc(wn))

Thus you must use elementwise multiplication to get

(bb(w1),bb(w2),...,bb(wn)).*(cc(w1),cc(w2),...,cc(wn))=

(bb(w1)*cc(w1),bb(w2)*cc(w2),...,bb(wn)*cc(wn)).

Best wishes

Torsten.